Need help choosing between 2 closed-cell foams

[chylld]

Hi All,

I'm stuck choosing between 2 closed-cell foams for use inside my car doors and floor. I've already laid down 2 layers of Dynamat Xtreme everywhere so I'm up to the stage of using foam to absorb airborne noise.

Given that I live in Australia, the 2 best closed-cell foam options I've found (prices in AUD) are:
1) Ensolite, from RAAMaudio (http://www.raamaudio.com/), 8.4 m2 @ 3mm thickness, PolyVinyl Chloride (PVC) / Nitril Butadiene Rubber (NBR) material, ~70kg/m3 density, price $138.68 incl. logistics
2) TF75PE, from Thermoplastic Foam Industries (http://www.tfifoam.com.au/), 8 m2 @ 3mm thickness, PolyEthylene (PE) material, ~80kg/m3 density, price $83.71 incl. logistics

A third option would be option #2 but in 5mm thickness, costing $102.50 incl. logistics.

As you can see, both materials are very similar - both closed-cell foam, comparable thickness (between #1 and #2) and similar density and coverage area. The main differences are the material and the price.

Furthermore, a quick and dirty test on the carsound.com forums showed that 2 layers of Ensolite provides twice the dB reduction of a single layer, so there is a benefit to added thickness here. My current inclination is to go with option 3 (#2 but in 5mm thickness) so as to avoid having to apply 2 layers of the thinner stuff for the same effect.

Opinions?

[chylld]

well, after a day of deliberation, i have opted for option #1: the Ensolite from RAAMaudio. my reasons are two-fold:

1) Rick's (RAAMaudio) experience in the area. He has tried several different types of foam with the exact same application in mind, and concluded that Ensolite was the best.
2) The TFI webpage lists dozens of application areas for their (essentially) single product line, which led me to believe that they didn't have a product tailored to the specific purpose (they also had taken zero nrc/similar sound measurements.)

I'm still interested in hearing opinions on this though :)

[arverson]

woah! 2 layers of SD everywhere and its still not quiet enuff for ya?! its a car mate, so expect SOME noise from the engine/tyre/etc. if u keep going, soon ull remove the engine from ur ride :P

havnt had much experience with raamats ensolite. but i have been in cars that have been heavily SD'd with raamats SD'ing and they sound fine to me.

no matter how much SD'ing u use, i dont think u can achieve a ABSOULTELY quiet car tho.. bcus, ITS A CAR!!

keep us updated on how the ensolite goes.

if the ensolite doesnt make ur ride quiet enuff, just turn up the volume ;)

:)

[chylld]

i found the culprit of the vast majority of the remaining resonance yesterday - the roof! unfortunately the roof isn't something i can simply remove myself as a DIY jobbie, so looking for a honda service rep who's willing to comply with an unusual request :)

ensolite should be shipped by the end of this week hopefully. it's more to remedy the doors which i've essentially turned into passive resonators - all hard surfaces inside and if you stick your ear up to the outside of the door with the stereo on and all the doors closed you can actually hear (and feel) the music quite well! so there's a hope that lining the inside of the door with ensolite will not only fix this a bit but also work the other way as well, stopping outside noise from coming in.

and yes i know it won't be possible to achieve perfection, but i'd prefer to chase it knowing i'll get much closer to it than i would have gotten if i just wanted to make things "a little bit better" :)